1. Field of the Invention
The invention relates to a semiconductor structure, and more particularly to a semiconductor structure with a spacer disposed between substrates and a fabrication method thereof.
2. Description of the Related Art
A conventional method of bonding is disclosed as follows. First, a photo-sensitive material is applied on a substrate. After photolithography, a patterned photo-sensitive material is formed on the substrate. Another substrate is then bonded to the substrate through the photo-sensitive material. However, the patterned photo-sensitive material with various thicknesses formed by photolithography is non-uniform, thus deteriorating bonding uniformity. Also, the photo-sensitive material is easily deformed (outflow) during the bonding process. Additionally, the bonding force of the photo-sensitive material to the substrates is weak.
Thus, development of a novel bonding method which is able to improve the bonding uniformity and the bonding force between the substrates and prevent material deforming (outflow) is desirable.